1. Field of the Invention
This invention relates to universal turret milling machines and more particularly, to an insert designed for horizontal insertion in, or mounted on a plate inserted in, a Bridgeport-type milling machine, to facilitate horizontal milling and drilling operations, in addition to conventional vertical machine operation. In a preferred embodiment tire horizontal insert is characterized by a generally cylindrical quill housing, the bottom surface of which is formed with a circular male pilot for insertion in a female pilot provided in the upper surface of the column element of the milling machine. The quill housing is bolted to the upper surface of the column element and the upper surface of the quill housing is shaped with a female pilot and a circular T-slot for receiving T-nuts and bolts which extend through the turret element of the milling machine. A standard or conventional quill assembly is horizontally slidably extendible from a quill bore provided in the quill housing and includes a rotatable spindle on the extendible end for mounting a milling tool or a drill. The splined end of the spindle is engaged by a standard or conventional electric milling machine motor mounted on the rear surface of the quill housing and rotates the spindle and an associated wormed power coupling, responsive to operation of the motor. Manipulation of a power feed control located on the quill housing exterior couples the wormed power coupling to a gear drive which is located in the quill housing and advances the quill assembly a predetermined distance from the quill bore by means of a rack and feed pinion gear. The wormed power coupling can thus be uncoupled from the gear drive train and the quill assembly manually advanced toward the workpiece by rotating a hand feed wheel selectively attached to a course hand feed shaft or a fine hand feed shaft, both of which extend from the quill housing and are each geared to the feed pinion gear. Manipulation of a speed control on the quill housing facilitates powered retraction and extension of the quill assembly into or from the quill bore at a selected speed and the advancing or retracting mode of the quill assembly can be controlled by means of a forward/reverse control. A spring-loaded and axially-shiftable feed stop adjusting screw, having a micrometer nut and a lock nut threadably mounted thereon, is horizontally mounted on the quill housing exterior adjacently parallel to a graduated scale. A toothed quill feed stop rack, mounted horizontally on a feed stop rack pinion gear located inside the quill housing, moves in concert with the quill assembly and is attached to a quill stop knob which extends outside the quill housing and encircles the feed stop adjusting screw. The lock nut and micrometer nut are positioned on the feed stop adjusting screw at a location corresponding to a selected location on the scale, to automatically halt advancement of the quill assembly from the quill bore. When the quill assembly advances a predetermined distance from the quill bore, either automatically by means of the motor or manually, by rotating the hand feed wheel, the quill stop knob extending from the stop rack engages the micrometer nut, causing the feed stop adjusting screw to shift against a spring and disengage a power feed handle provided on the housing which, in turn, disengages a toothed clutch in the gear train and automatically halts advancement of the quill assembly from the quill bore.
A Bridgeport-type universal milling machine is a machining tool commonly used, both in the United States and around the world, to perform a variety of machining operations, including drilling, tapping, reeming, milling and boring. The Bridgeport-type universal milling machine is very popular because it is extremely useful in performing smaller machining jobs, which usually make up the majority of work performed at a typical machine shop during any given year. However, one of the problems associated with conventional Bridgeport milling machines lies in the fact that these milling machines can only be used to perform machining operations in a vertical plane, or 45.degree. with respect to the vertical plane. The horizontal insert of this invention is designed to be inserted horizontally between the bottom column and upper turret portions of a universal turret milling machine, particularly a Bridgeport-type milling machine, or on a plate so inserted, to facilitate performing machining operations on a workpiece in a horizontal plane and at various selected angles with respect to the horizontal plane, in addition to performing machining operations on a workpiece in a vertical plane. In addition, the horizontal insert of this invention is designed to bring the cutting tool mounted on the quill assembly into closer proximity to the workpiece and the rigidity of the machine column, than is presently possible, and will allow heavier cuts and feeds in all machining operations.
2. Description of the Prior Art
Various milling machines and milling machine attachments are known in the art for facilitating various machining operations such as drilling, on a workpiece. U.S. Pat. No. 943,845, dated Dec. 21, 1909, to G. G. Porter and F. E. Cable, details a "Universal Milling Attachment" for use with standard milling machines. The universal milling attachment is characterized by a frame having an arbor rotatably mounted therein and provided at one end with a mechanism to connect it to the spindle of a milling machine. An adjustable member is attached to the frame for securing the frame to the overhanging arm of the milling machine. A tool holder having a driving mechanism is carried by the frame. U.S. Pat. No. 988,231, dated Mar. 28, 1911, to Arthur Vernet, describes a "Multiple Milling Machine", including a turret having a work table with multiple lateral arms connected to the turret and a tool holder carried by each arm. The turret is rotatable relative to the table, to bring any one of the tool holders in operative position with respect to the table. Some of the tool holders are each provided with multiple milling tools and are rotatable independently of the turret to bring any one of the milling tools into operative position. U.S. Pat. No. 1,004,620, dated Oct. 3, 1911, to Charles E. Berold, discloses a "Milling Attachment For Planing Machines". Disclosed is a universal milling head for attachment to the cross rail of a planing machine, such that the milling tools may be presented to the work piece at any desired angle with respect to the horizontal or vertical planes of the planing machine. U.S. Pat. No. 2,055,783, dated Sep. 29, 1936, to Arthur F. Bennett, details a "Machine Tool Structure" including an upright, rigid stand having an abutment, through which a rotatable spindle extends. An attachment is mounted on the abutment for cooperation with the spindle and the upright stand has a second abutment spaced from the first abutment for mounting the attachment in operative position. U.S. Pat. No. 2,519,206, dated Aug. 15, 1950, to Carl Van Ausdall, describes a "Milling Machine Attachment" for use with standard vertical milling machines. The milling machine attachment enlarges the scope of vertical milling machines by converting vertical milling operations such as sawing, slab milling and straddle milling into horizontal milling operations. U.S. Pat. No. 291,885, dated Nov. 10, 1959, to M. P. Budney, et al, discloses a "Milling Adaptor Head" for use with conventional milling machines and enabling milling machines to cut slots or grooves in concave surfaces of hollow objects such as cylinder tubes, rings and the like. U.S. Pat. No. 2,945,402, dated Jul. 19, 1960, to Fred G. Burg, discloses a "Movable Mounting For Machine Tool", which is capable of adequately supporting a heat and complex tool structure, such as a multiple spindle drill. The movable mounting for machine tool is characterized by a support for a rectilinear guide, a tool member provided in the guide for rectilinear movement therein, with the guide including a pair of opposed surfaces, between which the members are movable. A mechanism for clamping and preventing movement of the tool members is provided. U.S. Pat. No. 2,955,515, dated Oct. 11, 1960, to C. W. Berthiez, details "Machine Tools" for enabling a milling machine to effect both horizontal and vertical milling operations. The machine tools are characterized by an auxiliary head which is adapted for connection to the conventional head-stock of a horizontal boring machine. The auxiliary head has a mechanism for rotatably supporting at least one auxiliary horizontal tool spindle provided in the form of a hollow sleeve which coaxially surrounds the conventional boring spindle of the machine. U.S. Pat. No. 3,163,081, dated Dec. 29, 1964, to Stanley E. Vickers, discloses a "Right Angle Milling Head" adapted to be mounted on and powered drilling machines and the like. The milling head greatly increases the utility of drilling units by permitting them to be used for many types of milling operations. U.S. Pat. No. 4,709,465, dated Dec. 1, 1987, to Henry Lewis, et al, describes an "Interchangeable Spindle-Head Milling System", characterized by a master milling head capable of providing spindle driving power and up to a five axis movement to a wide range of individual spindle heads, each designed for a specific machining function and each selectively, interchangeably and automatically matable to the master head.
It is an object of this invention to provide an insert designed for horizontal insertion in a universal turret milling machine to facilitate performance of horizontal milling operations on a workpiece.
Another object of this invention is to provide an insert designed for horizontal insertion between the bottom column element and top turret of a Bridgeport-type milling machine, or on a plate so inserted, with a rotatable spindle to facilitate performance of horizontal milling operations on a workpiece.
Still another object of this invention is to provide a horizontal insert for universal turret milling machines, which insert is characterized by a generally cylindrical quill housing, including a horizontally-extendible quill assembly which is rotated by a motor mounted on the posterior surface of the quill housing and can be selectively advanced from or retracted into the quill housing, either manually or by means of the motor. The insert housing may be mounted between the bottom column element and top turret element of the machine or it may be mounted on a plate so mounted on the machine.
Yet another object of this invention is to provide a horizontal insert for universal turret milling machines, which horizontal insert is characterized by a generally cylindrical quill housing for mounting between the bottom column element and top turret element of a Bridgeport-type turret milling machine or on a plate so mounted, and includes a quill assembly which rotatably receives a spindle for mounting a milling tool and is selectively advanced in concert with the spindle a predetermined distance from a horizontal quill bore provided in the housing, by means of an electric quill drive motor mounted on the housing, or by means of a hand feed wheel provided on the housing.
A still further object of this invention is to provide a horizontal insert for universal turret milling machines, which insert is characterized by a quill assembly that is horizontally-extendible from a quill housing mounted in or on a Bridgeport-type milling machine. A spindle in the quill assembly receives cutting and milling tools and is rotated by splines shaped in one end thereof, powered by a motor mounted on the quill housing and the spindle is selectively coupled to a gear drive train located in the quill housing for advancing the quill assembly a predetermined distance from the quill housing to a workpiece. The quill assembly is selectively uncoupled from the gear drive train by means of a clutch for manually advancing the quill assembly from the quill housing by rotating a hand feed wheel provided on the housing.
Yet another object of this invention is to provide a horizontal insert for mounting between the turret and column of universal turret milling machines, or side-mounted on a plate so attached to the universal turret milling machine, which horizontal insert is characterized by a horizontally-extendible quill assembly that is selectively advanced from or retracted into a quill housing, either manually or by means of a drive motor attached to the housing, the advancement of which quill assembly may be automatically halted after advancing a predetermined distance from the housing, by means of a gear drive train uncoupling mechanism.